Graphene emerges as an ideal material for constructing high-performance strain sensors, due to its superior mechanical property and high conductivity. However, in the process of assembling graphene into macroscopic materials, its conductivity decreases significantly. Also, tedious fabrication process hinders the application of graphene-based strain sensors. In this work, we report a freestanding graphene assembled film (GAF) with high conductivity ((2.32 ± 0.08) × 10⁵ S m⁻¹). For the sensitive materials of strain sensors, it is higher than most of reported carbon nanotube and graphene materials. These advantages enable the GAF to be an ultra-low power consumption strain sensor for detecting airflow and vocal vibrations. The resistance of the GAF remains unchanged with increasing temperature (20–100 ℃), exhibiting a good thermal stability. Also, the GAF can be used as a strain sensor directly without any flexible substrates, which greatly simplifies the fabrication process in comparison with most reported strain sensors. Additionally, the GAF used as a pressure sensor with only ~4.7 μW power is investigated. This work provides a new direction for the preparation of advanced sensors with ultra-low power consumption, and the development of flexible and energy-saving electronic devices.

石墨烯因其优异的机械性能和高导电性而成为构建高性能应变传感器的理想材料。然而，在将石墨烯组装成宏观材料的过程中，其电导率显着下降。此外，繁琐的制造过程阻碍了基于石墨烯的应变传感器的应用。在这项工作中，我们报告了一种具有高电导率 ((2.32 ± 0.08) × 10 ⁵  S m ⁻¹). 对于应变传感器的敏感材料，它高于大多数报道的碳纳米管和石墨烯材料。这些优势使 GAF 成为用于检测气流和声音振动的超低功耗应变传感器。GAF的电阻随温度升高（20-100℃）保持不变，表现出良好的热稳定性。此外，GAF 可以直接用作应变传感器，无需任何柔性基板，与大多数报道的应变传感器相比，这大大简化了制造过程。此外，还研究了用作压力传感器的 GAF，功率仅为 ~4.7 μW。该工作为超低功耗先进传感器的制备、柔性节能电子器件的开发提供了新的方向。